Opening and closing mechanism for electronic shutter

ABSTRACT

A mechanical arrangement for electronically controlled photographic shutter, includes a ring rotatably mounted around the exposure aperture of the camera and, a pair of shutter blades coupled to each other and rotatably mounted respectively on fixed pins extending from said ring, one of which blades having an urging spring mounted thereon to act in the opening direction, a cam face adapted to be brought into engagement with said one of the blades having an urging spring in accordance with the movement of said ring to impart the blades a motion to open progressively, and a closing member capable of engaging, whenever a proper exposure has been obtained, the spring urged blade even in the midst of the blade&#39;&#39;s opening motion by the action of an electromagnet connected to an electronic exposure time control circuit thereby coercively displacing the shutter blades toward the closing directions. The above described arrangement is operative so that, upon generation of an electric signal indicating the completion of an exposure, the exposure aperture is closed without delay.

United States Patent 1191 Nov, 27, 1973 OPENING AND CLOSING MECHANISM F R EP TRQN Q jSH TTE [63] Continuation of Ser. No. ll8,902,-Feb. 25, 1971,

abandoned.

52 us. c1. 95/53 E, 95/53 EB, 95/63 51 Int. Cl. G031) .9/20 5 Field of Search. 95/53 R, 53 E, S3 E13,

[ 56] References Cited UNITED, STATES PATENTS 3,418,904 12/1968 Wick etal. 95/53 EB 3,356,004 12/1967 Kiper 95/63 3,439,595 4/1969 Kiper 95/63 X 3,507,201 4/1970 Fahlenberg et al 95/53 EB 3,559,547 I 2/1971 Rentschler..... 95/53 EB 3,541,942 11/1970 I Primary Examiner-Samuel S. Matthews Assistant ExaminerRussell Adams, J r.

. Attorney-John W. Malley et al.

[ 5 ABSTRACT A mechanical arrangement for electronically controlled photographic shutter, includes a ringrotatably mounted around the exposure aperture of the camera and, a pair of shutter blades coupled to each other and rotatably mounted respectively on fixed pins extend- "ing from said ring, one of which blades having'an urging'spring mounted thereon to act in the opening direction, a cam face adapted to be broughtinto engagement with said one of the blades having an urging spring in accordance with the movement of said ring I toimpart theblades amotion to open progressively,

and a closing member'capable of engaging, whenever a proper exposurehas been obtained, the spring urged blade even inthe-midst of the blades opening motion by the action of an electromagnet connected to an' aperture is closed without delay.

2 Claims, 2 Drawing Figures OPENING AND CLOSING MECHANISM FOR ELECTBON SHEITEER BACKGROUND O THE INVENTION, f

v This is a continuation of application Ser. No. Il8,902, filed Feb. 25, 197i, andnow abandoned.

FIELD 'OF THE INVENTION The present invention is concerned with a mechanism for opening and closing the blades of an electronic shutter, and more particularly itrelates, to a mechanical arrangement for an electronically controlled photo'- graphic shutter designed so that its exposure time is d eterminedin accordance'with the energizing time/of an electromagnet controlled by an electronic exposure time control circuit, said mechanical arrangement being operative so that both the diaphragm aperture and the exposure time are controlled simultaneously by a pair of shutter blades, and that upongeneration by said circuit of an electric signal indicating the termina-,

tion of an exposure the exposure aperture immediately in response to this signal.

DESCRIPTIONIOF THE PRIORaIt An electronically controlled photographic shutter areknown which are designed-to be'operativeso that is closed a high speed upon the generationof a closure signal. Also, such an electronic shutter requires two rings and a speed reducing means, and therefore, are sufficiently large space is required for accommodation of these component parts. In addition, the mechanism of such a shutter is complicated.

SUMMARY on THE INVENTION It is, therefore, a primary object of the present invention to eliminate the foregoing drawbacks and inconveniences inherent tothe mechanism of the conventional 7 electronic shutters and to provide a mechanical arrangement for electronically controlled. photographic shutters,,which is operative so that both the diaphragm aperture andthe exposuretime are controlled simultaneously by a pair of shutter blades and that upon generation, by an electronic exposure time control circuit, of a, signal indicating the ending of the required exposure aperture is closed immediately atahigh speed.

Another object of the present invention is to provide a mechanical arrangement of the type, described for electronically controlled photographic shutters, which a is designed so that a pair of shutter blades are rotatably about pins extending from a ring in such a way that the diaphragm aperture and theexposure time are both controlled simultaneously bya pairof shutterbla des and that upon generation by an electronic. exposure time control circuit 'of an electricsignal indicating the completion-of an exposure, the exposure aperture begins to be closed simultaneously therewith, is known.

these blades areoperatively coupled to each otherto effect openingmotions in compliance with a cam face and that, upon generation of a closure signal, the closingmemberis actuated immediately in response to this signal to move said pair of shutter blades in the same An example of such a conventional electronic shutter is providedwith; forgexample, two, independentfsector rings which are both capable of rotating around-the exposure aperture. One of these ringsis operativelycoupied to a speed reduction gear so that the rotation velocity of this ring may be kept within "a certain limit as ters, which isdesigned sothat-the shutter blades are closing direction and atahigh speed, starting from whatever opening positions which are assumed then by these blades.

A; still another object of the present invention is to provide a mechanical. arrangementof the type described for electronically controlled photographic shutopenedprogressively in compliance with a cam face it is rotated. Two shutterfblade's which constitute a'pair are rotatably supported by pins, respectively, which, in turn, are fixed-to thesetwo rings, respectively.

The conventional electronic shutter of the type .de-

scribed above is operated in sucha way thatas theshut ter release means is actuated, one ofthe two rings is rotated at a reduced speed due to the speed reduction gear coupled thereto. In accordance with the motion of which, in turn, is adapted toengage the moving blades.

A further objectof the present invention is to provide a mechanical arrangement of the type described for electronically controlledrphotographic shutters, which isdesigned sothat, at ,the timetheexposure aperture I is opened, the closingmember of the shutter-blades is this ring, the blades are rotated respectively about the I pinsserving as the'fulcrums andextending from the other of the rings. 3

On the other hand, when a closure signalis generated by said control circuit, the electromagnet is de-.

energized, and said theother ringwhich has tillthen been held stationary is relieved. of its lockedstater whereupon, this latter ringis rotated at a high speed.

In accordance with this motion of the other ring, the

shutter blades rotated respectively about the pins serving as the fulcrums of said one of therings in the direction opposite to that of their rotation described above, and thus the'exposure aperture is closed; In such a shutter of the type described, if a closuresignal isgenerated in the midst of the rotation at a reduced speed of said one of the rings, the exposure aperture is which represents the relative speeds of rotation of these two rings. Such a motion of the shutter-blades will. give improper exposure as compared with the instance where the exposure aperture is closed-immediatelyat nism of. FIG. lin its open position.

I closed in accordance with that motion ofthe blades U heldin the retreated position along the cam face and that,upon the generationof aclosure signal, said closing member immediately moves toward the center of the exposure aperture after passing beyond the cam face to engagethe shutter blades to thereby close the exposure aperture at'a. high speed.

I BRIEF DESCRIPTION OF DRAWINGS FIG. lis a somewhat diagram matic representation showing the shutter mechanism according entinvention in its cocked position; and I FIG. 2 is a somewhat diagrammatic representation, with. parts broken away, showing the shutter mechato the presshutter plate 1, an exposure aperture 1e, a lens mounting tube ,1 and an arcuate slot lg and a window 1h. A

ring- 2 has a fixed pin 2d extending from its rear surface,

a stopper 2b which extends through the arcuate slot lg to a' position beyond the front surface of said shutter plate 1, a gear portion 20 and a radially extending slot 2d. This ring 2 is mounted to the rear surfaceof the shutter plate 1 in such a way as to be rotatable around said exposure aperture 1e. A cocking shaft 3 having a gear 3a formed integrally therewith on the rear surface side of the shutter plate 1 is rotatably supported by this plate 1 and protrudes beyond the front surface thereof.

This cocking shaft 3 is normally urged to rotate clockwise bya spring 4 which is applied between said-pin lb and said cocking shaft 3. The gear 3a meshes with the gear portion 2( of the ring 2. A release lever 5 has a Thereafter, the bent portion'5aof the release lever 5 which till then has been in engagement with the stopper 2b of the ring 2 relieves its engagementwith said stop per 2b. As aresult, the ring 2 is rotated counterclockbent portion 5a which is engageable with the stopper 2b of the ring 2. This release lever 5 is rotatably mounted on a pin 6 which extends from the shutter plate 1. 'A I spring 7 applied between said pin la and said release lever 5 normally urges this lever 5 to rotate counterclockwise. A first shutter'blade 8 has a fixed pin 8b which is in engagement with the slot 2d of the ring 2 and another fixed pin 8a which extends from the, rear face of said first shutter blade 8. This first shutter blade 8 is rotatably'mo'unted on the rear surface of the shut: ter plate 1 by a pin 9 which extends from the rear'face of the ring 2.-A second shutter blade 10 has a slot 10a which engages said pin 8b and is rotatably mounted on the rear surface of the shutter plate 1 by a pin 11 which extends from the rear face of the ring 2. A spring 12 is applied between said pin 8a and said pin 11 to normally urge said first blade 8 to rotate counter-clockwise. A cam face 13 is formed on the body of the shutter not showmAs said ring 2 rotates, the pin 8b is displaced in wise via the gear 3a and the gear portion 2c by the restoring force of the tensioned spring 4. Since the pin 2a is displaced in its position in accordance with the movement of the ring 2, the lever 21 is rotated clockwise by the action of the spring 23. As a result, the engagement between the lever 21 and the pin 18b of the closing lever 18 is relieved. Also, the movement of said ring 2 causes the starter switch of the exposure time control circuit not shown to be actuated, and with this the counting of the delay time is started.

p The closing lever 1 8,after the relief of the locking by the lever 21, tends to rotate counter-clockwise by the action of the spring 20. However, the magnet lever its position along said cam face 13. A winding 14a of an electromagnet 14 is connected to a known, electronic exposure time control circuit not shown.

A magnetic lever 15 controlled by winding 14a has a bent armature portion 15a and a stopper portion 15b and is rotatably mounted on a pin.16 which extends from the shutter plate 1. This magnet lever 15 is normally urged clockwise by a spring 17. A closing lever 18 having a fixed pin 18a which extends from the front face thereof, another fixed pin 18b which extends from the rear face of said lever 18 and protrudes beyond the rear surface of the shutter plate 1 through a slot 1i, and

a closure action conducting face (hereinafter to be referred to simply as a work face) 180 which is engageable with said pin 8b. This closing lever 18 is rotatably mounted on a pin 19 which extends from the shutter plate 1. A spring 20 is applied between said pin 1d and said closing lever 18 and normally urges said closing lever 18 to rotate counter-clockwise. A lever 21 havingtwo arms which intrude into the travel paths of the pins 2a and 18b respectively is rotatably mounted on the rear surface of the shutter plate 1 by a pin 22 which extends from the rear surface of said plate 1. A spring 23 mally urges said lever 21 to rotate clockwise. Said arms of the lever 21 are engageably with the pin 20 of the ring 2 and the pin 18b of the closing lever l8, respectively.

The shutter having the foregoing. arrangement is operated as follows. The shutter-which is, in the cooked state as shown in FIG. 1 is released as the release lever 5 is rotated clockwise to thereby start its action.

As the release-lever 5 is rotated clockwise, a power switch of the exposure time control circuit not shown is closed first, to energize the electromagnet 14.

' is applied between the pin 1c and said lever 21 and noris being attracted to the energizedelectromagnet l4, and therefore the pin 18a of the closing lever 18 is retained in itsposition by the stopper 15b. On the other hand, the pin 8b of the first shutter blade 8 is caused to move along the cam face 13 by the movement of the ring 2. In accordancewith this movement of the pin 8b, therefore, the first shutter blade 8 is caused to rotate counterclockwise, about the pin9 serving as the fulcrum. It should be noted that said pin 8b is in engagement with the slot 10a of, the second shutter blade 10. Therefore, the second shutter blade 10 is caused, at the same time with the first shutter blade 8, to rotate clockwise about the pin 11' serving as the fulcrum.

In this way, the two shutter blades 8 and 10 act so as to open the exposure aperture 1e progressively in accordance with the cooperative actions of the movement of the ring 2 and the cam face 13, as shown in FIG. 2. When the amount of exposure reaches the proper value either duringthe course of opening or after the full openingof the exposure aperture l, said exposure time control circuit suspendsthe supply of power to the winding 14a of the electromagnet 14. As a result, this electromagnet 14 is deprived of its attracting force and accordingly. it relieves the magnet lever 15 of its engagement therewith. whereupon, the pin 18a of the closing lever 18 is relieved of its engagement with the stopper 15b of themagnet lever 15. As a'consequence, the closing lever 18 is caused to rotate coun' ter-clockwise by the spring force of the spring 20, During the foregoing part of operation, the work face 180 of the closing lever 18 urges the pin 8b which is ei- This counter-clockwise rotation of the lever 21 causes lever 15. Accordingly, the annature portion 15a is :urged against the core of the electromagnet 14 by the spring force ofthe spring 17. During this part of operation, the shutter is rendered to the condition as shown in FIG. 1. 1

v '5 a Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the. scope of the appended claims, the invention may be I tated in one direction around an exposure aperture upon shutter release operation; a first shutter blade 'rotatably mounted on said sector ring and normally urged by spring force to move toward the direction exposing said aperture, said firstshu'tter bladehaving a pin thereon; a second shutter blade rotatably mounted on said sector ring and interconnected with saidfirst shutter blade to be opened and'closed simultaneously with shutter plate; a cam face engaging said pin of said first shutter blade for controllingthe opening action of said first shutter blade'by-engaging this blade asthe sector ring is rotated; and a closing member engageable with said pin of said first shutter blade and operable to be locked during the energization of said electromagnet and to be relieved of its'locked state upon termination of said energization, saidclosing member being spring loaded so' that it is rotated by spring force when relieved from its locked state to engage said pin of said first shutter blade by said closing member to coercively move this blade in thedirection in which the exposure aperture is closed. V '2, An opening and closing mechanism for electronic shutters according to claim 1, further comprises a lever pivotably mounted on said shutter plate and engageable with said sector ring and said closing member, said lever being rotated in one direction to be disengaged from said closing member upon shutter release operaother direction, thereby causing said closing member to said first shutter blade in interlocking fashion with said 1 first shutter blade said first and second shutter blades respectively pivoted for said rotational motion to the of said first shutter tion and engaging said'sector ring to be rotated in an retreat to a position for non-engagement with said pin blade. a l 

1. An opening and closing mechanism for use with electronic shutters including an electronic exposure control circuit for determining the exposure time; said mechanism comprising an electromagnet connected to said electronic exposure control circuit; a shutter plate fixedly supporting said electromagnet; a sector ring mounted on said shutter plate and capable of being rotated in one direction around an exposure aperture upon shutter release operation; a first shutter blade rotatably mounted on said sector ring and normally urged by spring force to move toward the direction exposing said aperture, said first shutter blade having a pin thereon; a second shutter blade rotatably mounted on said sector ring and interconnected with said first shutter blade to be opened and closed simultaneously with said first shutter blade in interlocking fashion with said first shutter blade said first and second shutter blades respectively pivoted for said rotational motion to the shutter plate; a cam face engaging said pin of said first shutter blade for controlling the opening action of said first shutter blade by engaging this blade as the sector ring is rotated; and a closing member engageable with said pin of said first shutter blade and operable to be locked during the energization of said electromagnet and to be relieved of its locked state upon termination of said energization, said closing member being spring loaded so that it is rotated by spring force when relieved from its locked state to engage said pin of said first shutter blade by said closing member to coercively move this blade in the direction in which the exposure aperture is closed.
 2. An opening and closing mechanism for electronic shutters according to claim 1, further comprises a lever pivotably mounted on said shutter plate and engageable with said sector ring and said closing member, said lever being rotated in one direction to be disengaged from said closing member upon shutter release operation and engaging said sector ring to be rotated in another direction, thereby causing said closing member to retreat to a position for non-engagement with said pin of said first shutter blade. 